New PowerPivot Gallery Document

Hi,

when I try to create a "New PowerPivot Gallery" document, in a PowerPivot Gallery the following error is show when Excel is opening:

"We can't connect to http://server:port/sites/bi/PowerPivot Gallery/Forms/PowerPivot Gallery Document/Forms/template.xlsx. Please make sure you're using the correct web address".

Any help, please?

thanks,

José Cruz